Exploring the Demands of Urology: On-Call Compensation, Frequency, and Variability

INTRODUCTION

We investigate and analyze the available information regarding on-call patterns among urologists in the US.

METHODS

The AUA Workforce Workgroup collaborated with the AUA Data Team to analyze information from the 2022 AUA Census. Extracted data were analyzed to identify variability across gender, subspecialty, hours worked per week, AUA section, salary, and practice setting. We used χ2 tests to compare the groups with respect to each factor and defined statistical significance as a P value less than .05.

RESULTS

There were significant differences by gender and several other on-call factors including being required to take call to maintain hospital privileges (reported by 76% of female urologists vs 67% of male urologists; P = .026), getting paid for weekend call (28% of females vs 38% of males; P = .030), and making over $500 per day when taking weekend call (18% of females vs 32% of males; P < .001). Other differences existed between AUA sections in percentage of physicians receiving over $500 for weekday or weekend calls (P < .001). Lastly, practice setting differed in likelihood of being paid over $500 for weekday call (44% reported by private practice urologists, 7% reported by academic urologists, 14% reported by institutional urologists; P < .001).

CONCLUSIONS

These results underscore the substantial variability in on-call responsibilities and structure within the AUA workforce. Further research and regular participation in future censuses are recommended to continue to characterize these trends.

Burnout in Urological Education: An In-Depth Study of Residents and Fellows in the 2021 AUA Census

PURPOSE

Our goal was to explore the current trends in burnout, career choice regret, and well-being needs among urology residents and fellows, with specific emphasis on identifying key factors associated with burnout.

MATERIALS AND METHODS

The AUA Workforce Workgroup collaborated with the AUA Data Team to analyze data from the 2021 AUA Census, comprising a total of 243 residents and fellows. Key demographics, benefits and resources, career choice and debt, and burnout levels were analyzed, focusing on variables like gender, PGY (postgraduate year) level, debt burden, and personal health appointments.

RESULTS

Overall, 48% of residents and 33% of fellows met criteria for professional burnout, with a higher incidence among PGY-2 residents (70%). Depersonalization was particularly notable, with 74% of residents reporting medium to high levels. Burnout was significantly associated with difficulty attending personal health appointments (52% vs 34%) and lack of access to on-call rooms (54% vs 36%). In contrast, having children during residency was associated with lower burnout levels (30.8% vs 49.1%). Meal plans were ranked as the most desired benefit (32%), followed by ability to attend health appointments during work hours (17%) and paid family leave (16%). Educational debt over $150,000 was carried by 53% of residents and 48% of fellows. Interestingly, burnout rates showed no statistically significant difference in response rates across genders, relationship status, amount of educational debt, presence of paid maternity or paternity leave, and type of childcare arrangements.

CONCLUSIONS

Burnout remains a significant issue among urology trainees, with a complex interplay of factors like lack of personal time and provision of call rooms. The alarming rates of depersonalization and exhaustion highlight the urgency of implementing targeted interventions. Enhanced support systems, improved access to health care appointments, provision of call rooms, and debt management programs are recommended to alleviate the growing problem of professional burnout in the field of urology.

Factors Influencing Medical Students' Pursuit of Urology: Results From the AUA Census (2019-2021)

INTRODUCTION

Growing interest in urology among medical students highlights the need to understand factors influencing their specialty choice in today's context. We also investigate COVID-19's impact on these factors and any disparities among female and underrepresented in medicine (URiM) students.

METHODS

From 2019 to 2021, the AUA Annual Census survey included medical student-focused questions on demographics, career interests, and decision factors. Responses were analyzed.

RESULTS

One hundred ninety-two medical students participated. Thirty-six (24%) identified as female and 19 (13%) as URiM. Common reasons students would choose urology included surgical procedures (93%) and "good lifestyle" among surgical careers (85%), with no differences across gender or URiM status. Compared to pre-COVID (2019), during COVID (2020-2021), a greater proportion of students cited cutting-edge technology (90.1% vs 73.1%, P = .008) and surgical procedures (98.6% vs 87.2%, P = .008) as reasons to choose urology. Reasons for not choosing urology included competitiveness (48%) and poor lifestyle (26%). Female and URiM students expressed concern related to the combined "male dominated/gender discrimination/lack of diversity" aspect (female 33% vs male 3%, P < .001; URiM 25% vs non-URiM 7%, P = .04).

CONCLUSIONS

The AUA Census survey highlights factors influencing medical students' decisions regarding urology. Interest in procedural and technological aspects grew during COVID. Students expressed concern over the field's competitiveness and poor lifestyle, while also acknowledging that urology offers a favorable lifestyle compared to other surgical careers. Female and URiM students expressed ongoing concerns over the combined aspect of gender discrimination and/or the lack of existing diversity in the field.

Factors Related to Differential Treatment and Practice Limitations Amongst Urologists: A Report of American Urological Association 2021 Census Data

OBJECTIVE

To assess rates of urologist-reported differential treatment in practice and practice limitations based on characteristics of urologists... identity.

MATERIALS AND METHODS

The 2021 AUA Census samples were linked with the United States (US) practicing urologist population file and assigned proper sample weighting to adjust for non-response bias. Responses to 2 questions of the Census related to (1) (negative) differential treatment experienced in practice and (2) limitations in patients/diagnoses seen in practice due to different aspects of respondent...s identity were evaluated. Responses were stratified based on self-reported gender (female vs male) and race (White vs non-White); results were compared using a chi-squared test.

RESULTS

A total of 1742 urologists, representing 13,790 practicing US urologists through post-stratified weighting, responded to the Census. Overall, amongst those who answered the relevant questions, 16.3% reported having experienced differential treatment in practice due to their identity and 6.1% reported being limited in patients/diagnoses seen in practice due to their identity. Women were more likely than men to have experienced differential treatment (75.0% vs.ß10.2%, P.ß<.ß.001) and to be limited in patients/diagnoses seen in practice (27.0% vs.ß3.7%, P.ß<.ß.001). Similarly, non-White respondents were more likely than White urologists to both have experienced differential treatment (30.4% vs.ß14.1%, P.ß<.ß.001) and to be limited in patients/diagnoses seen in practice (12.8% vs.ß5.0%, P.ß<.ß.001).

CONCLUSION

Female and non-White urologists are more likely to experience differential treatment in their practice and limitations in the scope of their practice. Further studies are needed to characterize these experiences and explore the etiologies of these differences.

Professional Burnout of Advanced Practice Providers Based on 2019 American Urological Association Census Data

INTRODUCTION

Burnout has been recognized as an occupational hazard among health care professionals. The objective of this study was to assess the extent and pattern of burnout in advanced practice providers (APPs) in urology by analyzing American Urological Association Census data.

METHODS

The American Urological Association conducts an annual census survey to all providers in the urological care community, including APPs. In the 2019 Census, the Maslach Burnout Inventory questionnaire was included to measure burnout among APPs. Demographic and practice variables were assessed to establish correlating factors to burnout.

RESULTS

A total of 199 APPs (83 physician assistants and 116 nurse practitioners) completed the 2019 Census. Slightly more than 1 in 4 APPs experienced professional burnout (25.3% in physician assistants and 26.7% in nurse practitioners). Observed higher burnout rates were seen in APPs who were aged 45 to 54 (34.3%), women (29.6% vs 10.8% in men, p value <0.05), non-White (33.3% vs 24.9% in White), those who had 4-9 years of practice (32.4%) and those who practiced in academic medical centers (31.7%). Except for gender, none of the above observed differences were statistically significant. Using a multivariate logistic regression model, gender remained the only significant factor associated with burnout (women vs men with an odds ratio of 3.2 [95% confidence interval: 1.1-9.6]).

CONCLUSIONS

Overall, APPs in urological care reported lower levels of burnout than urologists; however, there was a higher chance of female APPs experiencing higher professional burnout in comparison to their male counterparts. Future studies are needed to investigate possible reasons for this finding.

Clinical challenges of scrotal lymphangioma in an adult: a rare case of scrotal swelling

Scrotal lymphangiomas represent an extremely rare cause of scrotal swelling. We report a case of scrotal lymphangioma in an 18-year-old male who presented with painful scrotal swelling. Scrotal ultrasound revealed a complex multicystic structure in the left hemiscrotum. The patient underwent successful surgical excision of the mass. Postoperatively, he developed a hydrocele which eventually spontaneously regressed. Histopathology confirmed the diagnosis. We outline the unusual presentation, characteristic imaging and histology findings, and surgical management of scrotal lymphangiomas. With this information, urologists may exercise a heightened level of awareness for this rare cause of scrotal swelling.

Determinants of gender disparities in scaling up the first 90 towards the UNAIDS 90-90-90 targets in South Africa: findings from the 2017 household-based national cross-sectional survey

BACKGROUND

The first 90 of UNAIDS 90-90-90 targets to have 90% of the people living with HIV know their status is an important entry point to the HIV treatment cascade and care continuum, but evidence shows that there is a large gap between males and females in this regard. It is therefore important to understand barriers and facilitators of achieving the first 90 target. This study examined determinants of the first 90 target among females and males in order to inform strategies aimed at improving the HIV cascade in South Africa.

METHODS

The data used in the analysis were obtained from a 2017 household-based cross-sectional nationally representative survey conducted using a multi-stage stratified cluster random sampling design. A series of hierarchical multiple logistic regression models were fitted to identify the determinants of the first 90 target by gender.

RESULTS

Overall, 84.8% of HIV-positive individuals aged 15 years and older were aware of their HIV status. Females were significantly more aware of their HIV status compared to males (88.7% vs 78.2%, p < 0.001). Both females aged 25 to 49 years [aOR = 3.20 (95% CI 1.35-7.57), p = 0.008], and 50 years and older [aOR = 3.19 (95% CI 1.04-9.76), p = 0.042] and males aged 25 to 49 years [aOR = 3.00 (95% CI 1.13-7.97), p = 0.028], and 50 years and older [aOR = 7.25 (95% CI 2.07-25.36), p = 0.002] were significantly more likely to know their HIV status compared to those aged 15 to 19 years. Males with tertiary education level were significantly more likely to be aware of their HIV positive status [aOR = 75.24 (95% CI 9.07-624.26), p < 0.001] compared to those with no education or with primary level education. Females with secondary [aOR = 3.28 (95% CI 1.20-8.99), p = 0.021] and matric [aOR = 4.35 (95% CI 1.54-12.37), p = 0.006] educational levels were significantly more likely to be aware of their HIV positive status, compared to those with no education or with primary level education.

CONCLUSION

Significant progress has been made with regards to reaching the UNAIDS first 90 target. In this context achieving the first 90 target is feasible but there is a need for additional interventions to reach the males especially youth including those with no education or low levels of education.

Does total testicular volume predict testicular volume difference in adolescent males with varicocele?

Introduction:

We evaluated the relationship between total testicular volume (TTV) and testicular volume differential (TVD) in adolescent males with varicocele. Both low TTV and high TVD have been independently associated with higher incidences of infertility later in life, but a predictive relationship between TTV and TVD directly has yet to be described.

Materials and Methods:

We retrospectively analyzed a database of Tanner 5 boys ages 16-21 who presented with varicocele at a single institution between 2009 and 2017. All patients had a scrotal sonogram prior to surgical intervention. TTV and TVD were calculated for each individual and four non-exclusive groupings of patients were created for statistical analysis. We chose 30 cc as a cut off value for low TTV based on prior studies.

Results:

209 patients met our inclusion criteria. Mean age was 18.3 years (16–21, SD 1.7) with a mean total testicular volume of 36 cc (13.5-78.2, SD 11.1). Cut off points of TVD of 20% and TTV of 30 cc were used to separate patients. There were 65 boys (31%) with TTV < 30 cc and 58 boys (28%) with TVD ≥ 20%. Among males with TTV < 30 cc, 23 (35%) had a TVD ≥ 20%. Among males with TTV ≥ 30 cc, 35 (24%) had a TVD ≥ 20%. The relationship between TVD and TTV was found to be non-significant (p > 0.05).

Discussion:

Adolescent varicoceles continue to pose a challenge to pediatric urologists. The dilemma of over-aggressive treatment has proven difficult to balance with the risk of infertility. We hoped that elucidating the relationship between TTV and TVD could be useful in identifying patients who are at greater risk for infertility while decreasing the need for more intrusive testing, such as semen analysis, in an adolescent population. We looked at the direct relationship between low TTV and high TVD. In our population, there was a non-significant relationship between TTV < 30 cc and TVD ≥ 20% (p > 0.05) indicating that in adolescents with varicocele, TTV and TVD are independent variables. Our study limitations include the inherent user dependent bias of ultrasound measurements and data collection at a single institution with high ethnic diversity, possibly not comparable to all patient populations.

Conclusions:

Low TTV (< 30 cc) itself is not predictive of high TVD (≥ 20%) in adolescent boys with varicocele, despite their reported independent associations with impaired fertility in other studies.

Chronic Methamphetamine Increases Alpha-Synuclein Protein Levels in the Striatum and Hippocampus but not in the Cortex of Juvenile Mice

Methamphetamine is the second most widely used illicit drug worldwide. More than 290 tons of methamphetamine was synthesized in the year 2005 alone, corresponding to approximately ~3 billion 100 mg doses of methamphetamine. Drug addicts abuse high concentrations of methamphetamine for months and even years. Current reports in the literature are consistent with the interpretation that methamphetamine-induced neuronal injury may render methamphetamine users more susceptible to neurodegenerative pathologies. Specifically, chronic exposure to psychostimulants is associated with increases in striatal alpha-synuclein expression, a synaptic protein implicated in the pathogenesis of neurodegenerative diseases. This raises the question whether methamphetamine exposure affects alpha-synuclein levels in the brain. In this short report, we examined alpha-synuclein protein and mRNA levels in the striatum, hippocampus and cortex of adolescent male mice following a neurotoxic regimen of methamphetamine (24mg/kg/daily/14days). We found that methamphetamine exposure resulted in a decrease in the monomeric form of alpha-synuclein (molecular species <19 kDa), while increasing higher molecular weight alpha-synuclein species (>19 kDa) in the striatum and hippocampus, but not in the cortex. Despite the elevation of high molecular weight alpha-synuclein species (>19 kDa), there was no change in the alpha-synuclein mRNA levels in the striatum, hippocampus and cortex of mice exposed to methamphetamine. The methamphetamine-induced increase in high molecular weight alpha-synuclein protein levels might be one of the causal mechanisms or one of the compensatory consequences of methamphetamine-mediated neurotoxicity.

Stability and Liftoff of a N2-in-H2 Jet Flame in a Vitiated Co-flow at Atmospheric Pressure

<p>The stability and liftoff characteristics of a nitrogen (N₂) diluted hydrogen (H₂) jet flame in a vitiated co-flow are investigated experimentally with particular attention focused on regimes where multiple stabilization mechanisms are active. Information gleaned from this research is instrumental for informing modeling approaches in flame transition situations when both autoignition and flame propagation influence combustion characteristics. Stability regime diagrams which outline the conditions under which the flame is attached, lifted, blown-out, and unsteady are experimentally developed and explored. The lifted regime is further characterized in determining liftoff height dependence on N₂ dilution, jet velocity, and co-flow equivalence ratio (or essentially, co-flow temperature). A strong sensitivity of liftoff height to N₂ dilution, jet velocity, and co-flow equivalence ratio is observed. Liftoff heights predicted by Kalghatgi’s correlation are unable to capture the effects of N₂ dilution on liftoff height for the heated co-flow cases. A uniquely formulated Damköhler number, where the chemical time scale is based on flame propagation rather than autoignition, was therefore developed which acceptably captures the effects of jet velocity, nitrogen dilution and environment temperature on liftoff height. Satisfactory agreement between the correlation results indicate that stabilization is dominated by propagation, and prior studies with similar flames, such as the research of Muñiz and Mungal (1997) indicate that the propagating flame is likely tribrachial.</p>

Effect of Pressure, Environment Temperature, Jet Velocity and Nitrogen Dilution on the Liftoff Characteristics of a N2-in-H2 Jet Flame in a Vitiated Co-flow

<p>The CO₂ emission prevention advantage of generating power with high hydrogen content fuels using gas turbines motivates an improved understanding of the ignition behavior of hydrogen in premixed and partially premixed environments. Hydrogen rich fueled flame stability is sensitive to operating conditions, including environment pressure, temperature, and jet velocity. Furthermore, when premixed or partially premixed operation is needed for nitric oxide emissions reduction, a diluent, such as nitrogen, is often added in allowing fuel/air mixing prior to combustion. Thus, the concentration of the diluent added is an additional independent variable on which flame stability dependence is needed. The focus of this research is on characterizing the dependence of hydrogen jet flame stability on environment temperature, pressure, jet velocity and diluent concentration by determining the dependence of the liftoff height of lifted flames on these 4 independent parameters. Nitrogen is used as the diluent due to its availability and effectiveness in promoting liftoff. A correlation modeling the liftoff height dependence on operating conditions is developed which emphasizes the factors that bear the greatest impact on ignition behavior.</p>

A UK consensus on the management of the bladder in multiple sclerosis

Bladder symptoms in multiple sclerosis (MS) are common and distressing but also highly amenable to treatment. A meeting of stakeholders involved in patients' continence care, including neurologists, urologists, primary care, MS nurses and nursing groups was recently convened to formulate a UK consensus for management. National Institute for Health and Clinical Excellence (NICE) criteria were used for producing recommendations based on a review of the literature and expert opinion. It was agreed that in the majority of cases, successful management could be based on a simple algorithm which includes using reagent sticks to test for urine infection and measurement of the post micturition residual urine volume. This is in contrast with published guidelines from other countries which recommend cystometry. Throughout the course of their disease, patients should be offered appropriate management options for treatment of incontinence, the mainstay of which is antimuscarinic medications, in combination, if necessary, with clean intermittent self-catheterisation. The evidence for other measures, including physiotherapy, alternative strategies aimed at improving bladder emptying, other medications and detrusor injections of botulinum toxin A was reviewed. The management of urinary tract infections as well as the bladder problems as part of severe disability were discussed and recommendations agreed.

Psychiatric symptoms among postpartum women in an urban hospital setting

The object of this study was to evaluate postpartum women for psychiatric symptomatology including cognitive disturbances, anxiety, depression, and anger to better meet their needs for support and involve them in the care of their infants. We interviewed 52 postpartum mothers at the Bronx Lebanon Hospital Center within 5 days of delivery and determined the presence of psychiatric symptoms using the 29-item Psychiatric Symptom Index. Despite the fact that adult mothers were happier they were pregnant (71.4% versus 29.4%; P = 0.010) and less likely to be worried about their baby's health (25.7% versus 52.9%; P = 0.003), adult mothers demonstrated higher depressive symptomatology ( P = 0.009), higher amounts of anger ( P = 0.004), and greater overall psychiatric symptomatology ( P = 0.005) than adolescent mothers. Mothers whose infants were in the neonatal intensive care unit did not report significantly higher psychiatric symptomatology than mothers whose infants were healthy. Physicians need to be aware of the high levels of depression and anger present among postpartum women so appropriate support can be given.

Arm and ankle blood pressure during caesarean section

BACKGROUND

We have previously reported that measurement of non-invasive blood pressure during caesarean section under spinal anaesthesia fails in over 50% of cases. We felt that errors would be less likely if blood pressure could be measured at the ankle as it is immobile during caesarean section. The purpose of our study was to determine whether blood pressure measurement at the ankle was equivalent to the arm.

METHOD

Following ethical approval, informed consent was obtained from 30 women scheduled for elective caesarean section. Two non-invasive blood pressure cuffs, one on the upper arm and one on the ankle, were used to measure blood pressures at three timed intervals: before spinal insertion, before surgery and after delivery of the neonate.

RESULTS

Using the method of Bland and Altman we found that there was only marginal agreement between the two methods. On eight out of 15 occasions where there was a greater than 20% fall in arm systolic blood pressure, this was not detected at the ankle.

CONCLUSION

We cannot recommend the use of the ankle to measure blood pressure during caesarean section.

Efficacy of Office Fulguration for Recurrent Low Grade Papillary Bladder Tumors Less Than 0.5 cm

PURPOSE

Recurrent superficial papillary bladder tumors are most commonly treated with transurethral resection with the patient under anesthesia. We report our experience with office fulguration of small, recurrent, low grade papillary tumors using flexible cystodiathermy.

MATERIALS AND METHODS

We conducted a prospective single institution analysis of 267 consecutive patients with superficial bladder cancer undergoing routine bladder cancer surveillance between January 1998 and December 2001. Cytological and histological recurrences were recorded. Selection criteria for office fulguration were less than 5 low grade appearing papillary tumors, tumor size less than 0.5 cm, negative urine cytology and patient desire. All patients completed initial treatment (transurethral resection, partial cystectomy and/or intravesical therapy) and a minimum of 6 months on surveillance without recurrence (median 11.57 months).

RESULTS

Flexible cystodiathermy for small, low grade, recurrent papillary tumors was efficacious and well tolerated. Of the 123 patients 46% experienced 1 or more tumor recurrences (range 1 to 11) in a median followup of 2.6 years. Of these 123, 74 (60%) underwent office cystodiathermy. No difference was seen in disease specific survival (p = 0.1633) or disease progression (p = 0.860). When stratified by risk of recurrence 202 of 267 patients at high risk (76%) with low grade papillary recurrence had similar rates of progression to patients at low risk (p = 0.9025). Median time from diagnosis was 6.84 years, and time from last tumor was 20.4 months.

CONCLUSIONS

Office cystodiathermy of small, low grade papillary recurrence is safe and efficacious in properly selected patients. This change in practice can potentially improve patient quality of life and have a major economic impact on health care.

Comparison of antibody functionality using different immobilization methods

This study investigates the influence of antibody immobilization methods on antigen capture. Adsorption and two surface chemistries, an aminosilane chemistry and a common heterobifunctional crosslinker (N-gamma-maleimidobutyryloxy-succinimide ester, GMBS), were compared and evaluated for their ability to immobilize antibodies and capture antigen. The role of protein A as an orienting protein scaffold component in each of these techniques was also evaluated. Through experimentation it was determined that the GMBS technique immobilized the highest amount of antibody and minimized nonspecific binding. For all techniques, the most functional antibodies were found to be those immobilized with protein A. Interestingly, the aminosilane technique demonstrated the highest antigen capture with antibody alone but also exhibited the highest level of nonspecific binding.

Encapsulation of recombinant adenovirus into alginate microspheres circumvents vector-specific immune response

Pre-existing immunity against adenoviruses may compromise the efficacy of adenoviral vectors for vaccination and gene therapy. The purpose of this study was to determine whether encapsulation of adenovirus recombinants into biodegradable alginate microparticles could circumvent the vector-specific immune response. Mice were immunized either intranasally (i.n.) or intraperitoneally (i.p.) with human adenovirus type 5 (HAd5), resulting in the development of virus-specific antibodies. Immunized and nai;ve mice were inoculated with AdCA36lacZ (an E1-deleted HAd5 recombinant containing the bacterial beta-galactosidase (LacZ) gene), encapsulated (E) into alginate microparticles, or nonencapsulated (NE) ie, as a virus suspension. LacZ expression in animals immunized once (1x) or twice (2x) with HAd5 and subsequently inoculated with NE-AdCA36lacZ (NE-Z) was significantly (P<0.001) reduced compared to those levels observed in NE-Z inoculated nai;ve mice, suggesting that the immune response against the vector adversely affected transgene expression. In contrast, there was only slight reduction (P>0.05) in LacZ expression in mice immunized 1x or 2x with HAd5 that were subsequently inoculated with E-AdCA36lacZ (E-Z) compared to those levels obtained in E-Z inoculated nai;ve animals. Similar results were obtained with i.n. or i.p. inoculated animals. These results indicate that microencapsulation of recombinant adenovirus effectively circumvented the vector-specific immune response.

Is visual search really like foraging?

The visual-search paradigm provides a controlled and easy to implement experimental situation in which to study the search process. However, little work has been carried out in humans to investigate the extent to which traditional visual-search tasks are similar to more general search or foraging. Here we report results from a task in which search involves walking around a room and leaning down to inspect individual locations. Consistent with more traditional search tasks, search time increases linearly with display size, and the target-present to target-absent search slope is 1:2. However, although rechecking of locations did occur, compared to more traditional search it was relatively rare, suggesting an increased role for memory.

Mice lacking desmocollin 1 show epidermal fragility accompanied by barrier defects and abnormal differentiation

The desmosomal cadherin desmocollin (Dsc)1 is expressed in upper epidermis where strong adhesion is required. To investigate its role in vivo, we have genetically engineered mice with a targeted disruption in the Dsc1 gene. Soon after birth, null mice exhibit flaky skin and a striking punctate epidermal barrier defect. The epidermis is fragile, and acantholysis in the granular layer generates localized lesions, compromising skin barrier function. Neutrophils accumulate in the lesions and further degrade the tissue, causing sloughing (flaking) of lesional epidermis, but rapid wound healing prevents the formation of overt lesions. Null epidermis is hyperproliferative and overexpresses keratins 6 and 16, indicating abnormal differentiation. From 6 wk, null mice develop ulcerating lesions resembling chronic dermatitis. We speculate that ulceration occurs after acantholysis in the fragile epidermis because environmental insults are more stringent and wound healing is less rapid than in neonatal mice. This dermatitis is accompanied by localized hair loss associated with formation of utriculi and dermal cysts, denoting hair follicle degeneration. Possible resemblance of the lesions to human blistering diseases is discussed. These results show that Dsc1 is required for strong adhesion and barrier maintenance in epidermis and contributes to epidermal differentiation.

Immunization with DNA, adenovirus or both in biodegradable alginate microspheres: effect of route of inoculation on immune response

To determine the potential for biodegradable alginate microspheres to be used as a delivery vehicle for DNA based vaccines, we constructed a plasmid, pMNe-gal-SV40, containing the bacterial beta-galactosidase (LacZ) gene under the control of the murine cytomegalovirus (MCMV) immediate-early promoter and the simian virus 40 (SV40) polyadenylation signal. The effect of the route of administration and co-administration of adenovirus on systemic and mucosal immune responses were investigated. Mice were inoculated orally, intranasally (i.n.), intramuscularly (i.m.), subcutaneously (s.c.) or intraperitoneally (i.p.) on days 0, 14 and 28 with microspheres containing plasmid DNA, bovine adenovirus type 3 (BAd3) or plasmid DNA + BAd3. Systemic routes of immunization (i.m., s.c. and i.p.) resulted in higher LacZ- or BAd3-specific IgG ELISA titers compared to those obtained by mucosal routes of inoculation (oral and i.n.). Mucosal immunization led to slightly higher titers of LacZ- or BAd3-specific IgA at mucosal sites compared to those obtained by the various systemic routes. All the routes of immunization induced LacZ-specific lymphoproliferation. Co-administration of BAd3 enhanced the LacZ-specific IgG response irrespective of the route of administration.

Biodegradable alginate microspheres as a delivery system for naked DNA

Sodium alginate is a naturally occurring polysaccharide that can easily be polymerized into a solid matrix to form microspheres. These biodegradable microspheres were used to encapsulate plasmid DNA containing the bacterial beta-galactosidase (LacZ) gene under the control of either the cytomegalovirus (CMV) immediate-early promoter or the Rous sarcoma virus (RSV) early promoter. Mice inoculated orally with microspheres containing plasmid DNA expressed LacZ in the intestine, spleen and liver. Inoculation of mice with microspheres containing both the plasmid DNA and bovine adenovirus type 3 (BAd3) resulted in a significant increase in LacZ expression compared to those inoculated with microspheres containing only the plasmid DNA. Our results suggest that adenoviruses are capable of augumenting transgene expression by plasmid DNA both in vitro and in vivo.

Desmosomal adhesion inhibits invasive behavior

Recent studies of human disease and transgenic animal experiments have clearly demonstrated the importance of desmosomes in normal tissue architecture. Furthermore, desmosomal components are down-regulated in certain types of carcinomas, suggesting a possible role for desmosomes in suppression of invasion and metastasis. However, there is no functional evidence to support such a hypothesis. To obtain such evidence, we needed to generate desmosomal adhesion in an invasive cell line. We show that expression of multiple desmosomal components (the desmosomal cadherins, desmocollin and desmoglein, and the armadillo protein, plakoglobin) in nonadhesive L929 fibroblasts generates adhesion in aggregation assays. This adhesion is specifically blocked by short peptides corresponding to the putative cell adhesion recognition sites of desmocollin and desmoglein. This result provides an experimental demonstration of the functional importance of the cell adhesion recognition sites of desmocollin and desmoglein and indicates that both desmosomal cadherins are specifically involved in this adhesion. Moreover, whereas parental L929 cells are strongly invasive into collagen gels, we show that invasion is substantially inhibited in cells transfected with desmosomal components. Invasion is restored by treating the transfected cells with anti-adhesion peptides, indicating that desmosomal adhesion specifically blocks invasion in culture. Our results support the suggestion that desmosomes have a role in suppression of tumor spreading.

Inhibition of neutrophil serine proteinases by suramin

Suramin, a hexasulfonated naphtylurea recently used as an anti-tumor drug, is a potent inhibitor of human neutrophil elastase, cathepsin G, and proteinase 3. The complexes it forms with these enzymes are partially active on synthetic substrates, but full inhibition takes place when elastase activity is measured with fibrous elastin or when cathepsin G activity is measured using platelet aggregation. One molecule of elastase binds four molecules of suramin with a Ki of 2 x 10(-7) M as determined by enzyme inhibition or intrinsic fluorescence enhancement of suramin. The binding curves show no sign of cooperativity or anticooperativity. The Ki for the complexes with cathepsin G and proteinase 3 are 8 x 10(-8) and 5 x 10(-7) M, respectively. Ionic strength increases the Ki of the elastase-suramin complex in a way that suggests that four of the six sulfonate groups of suramin form ionic interactions with basic residues of the enzyme and that at saturation almost all arginines of elastase form salt bridges with suramin. The neutrophil proteinase-inhibitory activity of suramin might be used to prevent tissue destruction and thrombus formation in diseases where massive infiltration and activation of neutrophils take place.

Desmosomes: differentiation, development, dynamics and disease

Recent evidence on the distribution of desmosomal glycoprotein isoforms that shows their combined expression in individual desmosomes has strengthened the belief that the latter are involved in epithelial differentiation and morphogenesis. It has been shown that cellular interactions and protein kinase C can modulate the adhesive properties of desmosomes in epithelial cell sheets. Genetic studies indicate the involvement of desmosomal components in cancer and epidermal diseases.

Purification, characterization, assembly and crystallization of assembled alfalfa mosaic virus coat protein expressed in Escherichia coli

The coast protein of alfalfa mosaic virus (AMV) was cloned and expressed in Escherichia coli as a fusion protein containing a 37 amino acid extension with a (His)6 region for affinity purification. About half of the expressed recombinant coat protein (rCP) was soluble upon extraction and half was insoluble in inclusion bodies. Western blot analysis confirmed the identity of the rCP and protoplast infectivity assays indicated that the rCP was biologically active in an early event of AMV infection, called genome activation. The rCP assembled into T = 1 empty icosahedral particles, as described previously for native coat protein. Empty particles formed hexagonal crystals that diffracted X-rays to 5.5 A resolution. The crystals of trypsin-treated particles of rCP appear to be isomorphous with crystals of trypsin-treated particles of native coat protein, Spherical particles containing RNA assembled when the rCP was combined with in vitro transcripts of AMV RNA4, the smallest naturally encapsidated AMV RNA. Bacilliform particles that resembled native virions assembled when the rCP was combined with transcripts of RNA1, the largest genomic RNA.

End-stage renal failure due to familial hypokalaemic interstitial nephritis with identical HLA tissue types

A family in which three siblings had familial hypokalaemic interstitial nephritis is described. There was a close linkage between the renal abnormality and tissue type inheritance.